Adhesive sheet, semiconductor device, and process for producing semiconductor device

ABSTRACT

An object of the present invention is to provide an adhesive sheet that can fill irregularities due to wiring of a substrate or a wire attached to a semiconductor chip, etc., does not form resin burrs during dicing, and has satisfactory heat resistance and moisture resistance. The present invention relates to an adhesive sheet comprising 100 parts by weight of a resin comprising 15 to 40 wt % of a high molecular weight component containing a crosslinking functional group and having a weight-average molecular weight of 100,000 or greater and a Tg of −50° C. to 50° C., and 60 to 85 wt % of a thermosetting component containing an epoxy resin as a main component, and 40 to 180 parts by weight of a filler, the adhesive sheet having a thickness of 10 to 250 μm.

This application is a Divisional application of prior application Ser.No. 11/578,939, filed Oct. 19, 2006, the contents of which areincorporated herein by reference in their entirety. No. 11/578,939 is aNational Stage Application filed under 35 USC 371, of International(PCT) Application No. PCT/JP2005/007529, filed Apr. 20, 2005.

TECHNICAL FIELD

The present invention relates to an adhesive sheet, a semiconductordevice, and a process for producing a semiconductor device.

BACKGROUND ART

In recent years, accompanying a reduction in the size of semiconductorpackages, a CSP (Chip Size Package) having a similar size to that of asemiconductor chip and, furthermore, a stacked CSP in whichsemiconductor chips are stacked in multiple tiers have become widespread(ref. e.g. Japanese Patent Application Laid-open Nos. 2001-279197,2002-222913, 2002-359346, 2001-308262, and 2004-72009). As examplesthereof, there are a package shown in FIG. 1 in which a semiconductorchip A1 is stacked on a substrate 3 having irregularities due to wiring4, etc., a package shown in FIG. 2 employing at least two semiconductorchips A1 of identical size in which another chip is further stacked overa semiconductor chip having irregularities due to a wire 2, etc. In suchpackages, an adhesive sheet in which the irregularities are embedded andthat can ensure that there is insulation from the upper semiconductorchip is required. In FIG. 1 and FIG. 2, b1 is an adhesive.

In order to fill irregularities due to wiring, wires, etc. it isnormally necessary to increase the thickness of the adhesive sheet tomore than the height of the irregularities, and to reduce the meltviscosity of the adhesive sheet, thus improving the filling properties.However, an adhesive sheet having a large thickness and a low meltviscosity has the problems that the edges of a semiconductor chipobtained by dicing a wafer and the adhesive sheet are badly damaged andthe amount of filamentous waste (resin burrs) increases.

That is, a dicing step normally involves laminating together a wafer, anadhesive sheet, and a dicing tape at 0° C. to 80° C., thensimultaneously cutting them by means of a rotating blade, and carryingout washing, thus giving an adhesive-equipped semiconductor chip. Insome cases, cutting waste from the adhesive sheet or the wafer becomesattached to a groove of the dicing tape formed after the above cuttingprocess, and it becomes detached from the dicing tape during washingafter cutting or when picking up the semiconductor chip, thus formingfilamentous waste (resin burrs), which becomes attached to thesemiconductor chip and thus contaminates an electrode, etc.

From the above-mentioned points, there is a desire for an adhesive sheetthat has excellent dicing properties and excellent filling propertiesfor irregularities due to wiring, wires, etc., and has satisfactory heatresistance and moisture resistance.

DISCLOSURE OF THE INVENTION

It is an object of the present invention to provide an adhesive sheetthat can fill irregularities due to wiring of a substrate or a wireattached to a semiconductor chip, etc., does not form resin burrs duringdicing, and has satisfactory heat resistance and moisture resistance.

The present inventors of the present invention have found that, inaccordance with the use of an adhesive sheet having a specified resincomposition, it is possible to prevent the occurrence of resin burrsduring dicing, and fill irregularities due to wiring of a substrate or awire attached to a semiconductor chip, etc. (embedding a projectionwithin the adhesive sheet or filling a recess with an adhesive sheet),and the present invention has thus been accomplished.

That is, the present invention relates to an adhesive sheet comprising100 parts by weight of a resin comprising 15 to 40 wt % of a highmolecular weight component containing a crosslinking functional groupand having a weight-average molecular weight of 100,000 or greater and aTg of −50° C. to 50° C., and 60 to 85 wt % of a thermosetting componentcontaining an epoxy resin as a main component, and 40 to 180 parts byweight of a filler, the adhesive sheet having a thickness of 10 to 250μm.

Furthermore, the present invention relates to the adhesive sheet,wherein prior to curing the storage modulus by a dynamic viscoelasticitymeasurement at 25° C. is 200 to 3,000 MPa, and the storage modulus by adynamic viscoelasticity measurement at 80° C. is 0.1 to 10 MPa.

Moreover, the present invention relates to the adhesive sheet, whereinthe storage modulus by a dynamic viscoelasticity measurement at 170° C.subsequent to curing is 20 to 600 MPa.

Furthermore, the present invention relates to the adhesive sheet,wherein the melt viscosity at 100° C. prior to curing is 1,000 to 7,500Pa·s.

Moreover, the present invention relates to the adhesive sheet, whereinit comprises 100 parts by weight of the resin and 60 to 120 parts byweight of the filler.

Furthermore, the present invention relates to the adhesive sheet,wherein the filler has a Mohs' hardness of 3 to 8.

Moreover, the present invention relates to the adhesive sheet, whereinthe filler has an average particle size of 0.05 to 5 μm and a specificsurface area of 2 to 200 m²/g.

Furthermore, the present invention relates to the adhesive sheet,wherein it is used in steps of laminating together a wafer, an adhesivesheet, and a dicing tape at 0° C. to 80° C., cutting the wafer, theadhesive sheet, and the dancing tape simultaneously by means of arotating blade to give an adhesive-equipped semiconductor chip, and thenbonding this adhesive-equipped semiconductor chip to a substrate orsemiconductor chip having irregularities with a load of 0.001 to 1 MPaso as to fill the irregularities with adhesive.

Moreover, the present invention relates to a multi-layer adhesive sheethaving a structure in which a first adhesive layer and a second adhesivelayer are directly or indirectly layered, at least the second adhesivelayer comprising the above adhesive sheet, and an amount of flow A μmand a thickness a μm of the first adhesive layer and an amount of flow Bμm and a thickness b μm of the second adhesive layer satisfying therelationships A×3<B and a×2<b.

Furthermore, the present invention relates to a multi-layer adhesivesheet having a structure in which a first adhesive layer and a secondadhesive layer are directly or indirectly layered, at least the secondadhesive layer comprising the above adhesive sheet, and a melt viscosityα Pa·s and a thickness a μm of the first adhesive layer and a meltviscosity βPa·s and a thickness b μm of the second adhesive layersatisfying the relationships α>β×3 and a×2<b.

Moreover, the present invention relates to the multi-layer adhesivesheet, wherein when a wafer, the adhesive sheet, and a dicing tape arelaminated together, the first adhesive layer is on the side that is incontact with the wafer, and the second adhesive layer is on the sidethat is in contact with the dicing tape.

Furthermore, the present invention relates to a process for producing asemiconductor device, the process comprising steps of laminating awafer, the adhesive sheet, and a dicing tape at 0° C. to 80° C., thencutting the wafer, the adhesive sheet, and the dancing tapesimultaneously by means of a rotating blade to give an adhesive-equippedsemiconductor chip, and then bonding this adhesive-equippedsemiconductor chip to a substrate or a semiconductor chip havingirregularities at a load of 0.001 to 1 MPa so as to fill theirregularities with adhesive.

Moreover, the present invention relates to the process for producing asemiconductor device, wherein when the adhesive-equipped semiconductorchip is bonded to the substrate or semiconductor chip havingirregularities, the irregularities are heated.

Furthermore, the present invention relates to a semiconductor deviceformed by bonding a semiconductor chip and a substrate, or asemiconductor chip and a semiconductor chip using the adhesive sheet.

The disclosures of the present application relate to subject matterdescribed in Japanese Patent Application No. 2004-124118 filed on Apr.20, 2004 and Japanese Patent Application No. 2004-351605 filed on Dec.3, 2004, and the contents of the disclosures therein are incorporatedherein by reference.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a sectional view showing one embodiment of a CSP.

FIG. 2 is a sectional view showing one embodiment of a stacked CSP.

FIG. 3 is a sectional view showing one embodiment of an adhesive sheet,a semiconductor wafer, and a dancing tape of the present invention.

FIG. 4 is a sectional view showing one embodiment of a multi-layeradhesive sheet, a semiconductor wafer, and a dicing tape of the presentinvention.

FIG. 5 is a schematic diagram showing one embodiment of a step whenbonding an adhesive-equipped semiconductor chip employing an adhesivesheet of the present invention to a wire-bonded chip.

FIG. 6 is a sectional view showing one embodiment of a substratefilm-equipped adhesive sheet of the present invention.

FIG. 7 is a sectional view showing one embodiment of a substratefilm-equipped multi-layer adhesive sheet of the present invention.

FIG. 8 is a sectional view showing one embodiment of anadhesive-equipped semiconductor chip of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

The adhesive sheet of the present invention comprises 100 parts byweight of a resin comprising 15 to 40 wt % of a high molecular weightcomponent containing a crosslinking functional group and having aweight-average molecular weight of 100,000 or greater and a Tg of −50°C. to 50° C., and 60 to 85 wt % of a thermosetting component containingan epoxy resin as a main component, and 40 to 180 parts by weight of afiller, the adhesive sheet having a thickness of 10 to 250 μm.

With regard to the adhesive sheet of the present invention, componentsthereof are not particularly limited as long as it is an adhesive sheetcomprising 100 parts by weight of a resin containing 15 to 40 wt % of ahigh molecular weight component containing a crosslinking functionalgroup and having a weight-average molecular weight of 100,000 or greaterand a Tg of −50 to 50° C., and 60 to 85 wt % of a thermosettingcomponent having an epoxy resin as a main component, and 40 to 180 partsby weight of a filler, but in addition to the high molecular weightcomponent, the thermosetting component, and the filler, the adhesivesheet may contain a curing accelerator, a catalyst, an additive, acoupling agent, etc. since an appropriate tack strength can be impartedand handling properties as a sheet can be improved.

Examples of the high molecular weight component include a polyimideresin, (meth)acrylic resin, urethane resin, polyphenylene ether resin,polyetherimide resin, phenoxy resin, and modified polyphenylene etherresin that have a crosslinking functional group such as an epoxy group,an alcoholic or phenolic hydroxyl group, or a carboxyl group, but it isnot limited to these examples.

The above-mentioned adhesive sheet has good filling properties when thehigh molecular weight component is contained at 15 to 40 wt % of theresin, and the content of the high molecular weight component ispreferably 20 to 37 wt %, and more preferably 25 to 35 wt %.

The high molecular weight component of the present invention is a highmolecular weight component having a Tg (glass transition temperature) of−50° C. to 50° C., containing a crosslinking functional group, andhaving a weight-average molecular weight of 100,000 or greater.

As the high molecular weight component, for example, an epoxygroup-containing (meth)acrylic copolymer obtained by polymerization ofmonomers that include a functional monomer such as glycidyl acrylate orglycidyl methacrylate and having a weight-average molecular weight of100,000 or greater, etc. is preferable. Examples of the epoxygroup-containing (meth)acrylic copolymer that can be used herein includea (meth)acrylic acid ester copolymer and an acrylic rubber, and theacrylic rubber is preferable.

The acrylic rubber is a rubber having an acrylic acid ester as a maincomponent and mainly comprising a copolymer of butyl acrylate andacrylonitrile, etc. or a copolymer of ethyl acrylate and acrylonitrile,etc.

When the Tg of the high molecular weight component exceeds 50° C., theflexibility of the sheet might be degraded, and when the Tg is less than−50° C., since the flexibility of the sheet is too high, it becomesdifficult to cut the sheet when dicing a wafer, and burrs might easilyoccur.

Furthermore, the weight-average molecular weight of the high molecularweight component is preferably at least 100,000 but no greater than1,000,000; when the molecular weight is less than 100,000, the heatresistance of the sheet might be degraded, and when the molecular weightexceeds 1,000,000, the flow of the sheet might be degraded. Theweight-average molecular weight is a polystyrene-basis value, and isdetermined by gel permeation chromatography (GPC) using a calibrationcurve obtained using a standard polystyrene.

It is preferable for the high molecular weight component to have a Tg of−20° C. to 40° C. and a weight-average molecular weight of 100,000 to900,000 since the adhesive sheet is easily cut during wafer dicing,there is little generation of resin waste, and the heat resistance ishigh, and it is more preferable for the high molecular weight componentto have a Tg of −10° C. to 40° and a molecular weight of 200,000 to850,000.

With regard to the thermosetting component used in the presentinvention, an epoxy resin having the heat resistance and moistureresistance required when mounting a semiconductor chip is preferable. Inthe present invention, the ‘thermosetting component containing an epoxyresin as a main component’ includes an epoxy resin curing agent. Theepoxy resin is not particularly limited as long as it exhibits anadhesive action upon curing. A difunctional epoxy resin such as abisphenol A epoxy resin, a bisphenol F epoxy resin, or a bisphenol Sepoxy resin, a novolac epoxy resin such as a phenol novolac epoxy resinor a cresol novolac epoxy resin, etc. may be used. Furthermore, agenerally known epoxy resin such as a polyfunctional epoxy resin, aglycidyl amine type epoxy resin, a hetero ring-containing epoxy resin,or an alicyclic epoxy resin may be employed.

It is preferable for the epoxy resin to have a molecular weight of 1,000or less, and more preferably 500 or less, in particular since theflexibility of a film in a B-stage state is high. It is also preferableto use in combination 50 to 90 parts by weight of a bisphenol A orbisphenol F epoxy resin having excellent flexibility and a molecularweight of 500 or less and 10 to 50 wt % of a polyfunctional epoxy resinhaving a molecular weight of 800 to 3,000, which has excellent heatresistance when cured.

With regard to the epoxy resin curing agent, a normally used knowncuring agent may be used, and examples thereof include amines,polyamide, acid anhydrides, polysulfide, boron trifluoride, bisphenolssuch as bisphenol A, bisphenol F, and bisphenol S, which have at leasttwo phenolic hydroxyl groups per molecule, and phenolic resins such as aphenol novolac resin, a bisphenol A novolac resin, and a cresol novolacresin.

Furthermore, the adhesive sheet of the present invention comprises afiller in order to improve the dicing properties of the adhesive sheetin a B-stage state, improve the handling properties of the adhesivesheet, improve thermal conductivity, adjust melt viscosity, impartthixotropy, etc., and preferably comprises an inorganic filler.

Examples of the inorganic filler include aluminum hydroxide, magnesiumhydroxide, calcium carbonate, magnesium carbonate, calcium silicate,magnesium silicate, calcium oxide, magnesium oxide, alumina, aluminumnitride, aluminum borate whisker, boron nitride, crystalline silica,amorphous silica, and antimony oxide. In order to improve thermalconductivity, alumina, aluminum nitride, boron nitride, crystallinesilica, amorphous silica, etc. are preferable. In order to adjust meltviscosity or impart thixotropy, aluminum hydroxide, magnesium hydroxide,calcium carbonate, magnesium carbonate, calcium silicate, magnesiumsilicate, calcium oxide, magnesium oxide, alumina, crystalline silica,amorphous silica, etc. are preferable. Furthermore, in order to improvedicing properties, alumina and silica are preferable.

In the present invention, it is preferable for the filler to becontained at 40 to 180 parts by weight relative to 100 parts by weightof the resin since the dicing properties are improved, the storagemodulus after curing the adhesive sheet becomes 50 to 600 MPa at 170°C., and the wire bonding properties improve. The amount of filler ismore preferably 60 to 160 parts by weight relative to 100 parts byweight of the resin, and yet more preferably 60 to 120 parts by weight.

It is preferable for the amount of filler added to be no greater than180 parts by weight since when it becomes large, the problems of thestorage modulus of the adhesive sheet increasing excessively, theadhesion deteriorating, the electrical properties being degraded due toremaining voids, etc. easily occur. When the amount of filler added issmall, resin burrs tend to be easily formed during dicing.

The present inventors have found that in accordance with addition of thefiller, the formation of resin burrs in the dicing step below can begreatly suppressed. That is, when dicing, a step in which a wafer, anadhesive sheet, and a dicing tape are simultaneously cut by means of arotating blade and washed to give an adhesive-equipped semiconductorchip is normally employed. Cutting waste from the adhesive sheet or thewafer becomes attached to a groove in the dicing tape that is formedafter cutting, and it becomes detached from the dicing tape in afilamentous state during cutting, washing after cutting, or pickup ofthe chip, thus forming resin burrs in some cases.

When the adhesive sheet of the present invention is used, particularlysince it contains 40 to 180 parts by weight of silica, alumina filler,etc. relative to 100 parts by weight of the resin, the cutting wastefrom the resin or silicon formed during dicing is in the form of finepowder with the filler as a primary component, and it becomes easy toremove it together with washing water. Therefore, in accordance with useof the adhesive sheet of the present invention, the amount of cuttingwaste remaining on the dicing tape is small. Furthermore, since thissmall amount of cutting waste sticks to the dicing tape, it is resistantto becoming detached from the dicing tape in a filamentous state.

On the other hand, when it contains no filler, since cutting waste is inthe form of a clay and is not removed together with washing water, alarge amount of cutting waste becomes attached to the dicing tape. Sincethis cutting waste easily becomes detached from the dicing tape whenwashing or picking up the semiconductor chip, a lot of resin burrs aregenerated.

Furthermore, in the present invention, since the adhesive sheet containsthe filler, no resin remains on the rotating blade when cutting thesheet, and the adhesive sheet can be cut well in a short period of timewhile polishing the rotating blade. It is therefore preferable, from theviewpoint of the effect of polishing the rotating blade and the ease ofcutting the adhesive sheet, for the adhesive sheet to contain a hardfiller, it is more preferable for it to contain a filler having a Mohs'hardness (scale of 10) of 3 to 8, and it is yet more preferable for itto contain a filler having a Mohs' hardness of 6 to 7. When the Mohs'hardness (scale of 10) of the filler is less than 3, the effect ofpolishing the rotating blade is small, whereas when the Mohs' hardnessexceeds 8, the durability of the rotating blade for dicing tends todeteriorate. Examples of fillers having a Mohs' hardness of 3 to 8include calcite, marble, gold (18K), iron, etc. (Mohs' hardness 3),fluorite, pearl, etc. (Mohs' hardness 4), apatite, glass, etc. (Mohs'hardness 5), orthoclase, opal, etc. (Mohs' hardness 6), and silica,quartz, tourmaline, etc. (Mohs' hardness 7), and among them silica,which has a Mohs' hardness of 7, is preferable since it is inexpensiveand readily available.

If the average particle size of the filler is less than 0.05 μm, ittends to become difficult to impart flowability to the adhesive sheetwhile imparting to the filler the effect of polishing the rotatingblade, whereas if the average particle size exceeds 5 μm, it becomesdifficult to reduce the thickness of the adhesive sheet, and it tends tobecome difficult to maintain smoothness on the surface of the adhesivesheet. It is therefore preferable, from the viewpoint of the flowabilityand the surface smoothness of the adhesive sheet, for the averageparticle size of the filler to be 0.05 to 5 μm. Furthermore, from theviewpoint of excellent flowability, the average particle size preferablyhas a lower limit of 0.1 μm, and particularly preferably 0.3 μm.Moreover, from the viewpoint of smoothness, the average particle sizepreferably has an upper limit of 3 μm, and particularly preferably 1 μm.

In the present invention, the average particle size of the filler ismeasured using a laser diffraction particle size distribution analyzer(Microtrac, manufactured by Nikkiso Co., Ltd.). Specifically, 0.1 to 1.0g of the filler is weighed, dispersed by means of ultrasound, and thensubjected to measurement of particle size distribution, and a particlesize that gives a 50% cumulative weight in the distribution is definedas the average particle size.

With regard to the specific surface area of the filler, in the samemanner as for the average particle size of the filler, from theviewpoint of the flowability and the surface smoothness, it ispreferably 2 to 200 m²/g, and from the viewpoint of the flowability theupper limit of the specific surface area is more preferably 50 m²/g, andparticularly preferably 10 m²/g.

In the present invention, the specific surface area (BET specificsurface area) is a value obtained from the Brunauer-Emmett-Tellerequation by measuring surface area as a result of making nitrogen adsorbon an inorganic filler, and can be measured by a commercial BET system.

The adhesive sheet of the present invention may be obtained by mixingand kneading the above-mentioned high molecular weight component,thermosetting component with an epoxy resin as a main component, filler,and other components in an organic solvent to give a varnish, thenforming a layer of the above-mentioned varnish on a substrate film,drying by heating, and then removing the substrate. The above-mentionedmixing and kneading may be carried out by employing in combination asappropriate dispersers such as a normal stirrer, a mortar and pestlemachine, a three-roll mill, and a ball mill. The above-mentioned dryingby heating is not particularly limited as long as it is carried outunder conditions in which the solvent used vaporizes sufficiently, butit is normally carried out by heating at 60° C. to 200° C. for 0.1 to 90minutes.

The organic solvent used for preparation of the varnish in production ofthe adhesive sheet, that is, a residual volatile component afterpreparation of the adhesive sheet, is not limited as long as materialscan be dissolved, kneaded, or dispersed uniformly, and a conventionallyknown solvent may be used. Examples of such a solvent includedimethylformamide, dimethylacetamide, N-methylpyrrolidone, ketonesolvents such as acetone, methyl ethyl ketone, and cyclohexanone,toluene, and xylene. It is preferable to use methyl ethyl ketone,cyclohexanone, etc., since the drying speed is high and the cost is low.

The amount of organic solvent used is not particularly limited as longas the residual volatile content in the prepared adhesive sheet is 0.01to 3 wt % relative to the total weight, but it is preferable from theviewpoint of heat resistance reliability for it to be 0.01 to 2 wt %relative to the total weight, and more preferably 0.01 to 1.5 wt %relative to the total weight.

The thickness of the adhesive sheet is 10 to 250 μm in order thatirregularities due to gold wire attached to a wiring circuit of asubstrate or a lower layer semiconductor chip can be filled. If it isthinner than 10 μm, the effect of relieving stress and the adhesion tendto become poor, and if it is thicker than 250 μm, not only is ituneconomic, but also a requirement for a small size semiconductor devicecannot be met. It is preferable for it to be 20 to 100 μm, and morepreferably 40 to 80 μm, from the viewpoint of high adhesion and a thinsemiconductor device.

In the present invention, it is preferable if the storage modulus bydynamic viscoelasticity measurement at 25° C. of the adhesive sheetprior to curing (in a B-stage state) is 200 to 3,000 MPa since thedicing properties are excellent. It is more preferable for it to be 500to 2,000 MPa from the viewpoint of excellent dicing properties andexcellent adhesion to a wafer. If the storage modulus by dynamicviscoelasticity measurement at 80° C. of the adhesive sheet prior tocuring (in a B-stage state) is 0.1 to 10 MPa, laminating to a wafer at80° C. is possible. It is particularly preferable for it to be 0.5 to 5MPa from the viewpoint of high adhesion to a wafer.

In the present invention, it is preferable for the storage modulus bydynamic viscoelasticity measurement at 170° C. of the adhesive sheetsubsequent to curing (in a C-stage state) is 20 to 600 MPa in order toobtain good wire bonding properties. The storage modulus is morepreferably 40 to 600 MPa, and yet more preferably 40 to 400 MPa.

Modulus of elasticity may be measured using a dynamic viscoelastometer(DVE-V4, manufactured by Rheology Co., Ltd.) (sample size: length 20 mm,width 4 mm, temperature range −30° C. to 200° C., rate of temperatureincrease 5° C./min, tensile mode, 10 Hz, automatic static load).

The adhesive sheet of the present invention may be used as a multi-layeradhesive sheet having a multi-layer structure such as, for example, alaminate of two or more of the above-mentioned adhesive sheets or alaminate of a plurality of sheets including the adhesive sheet of thepresent invention and another adhesive sheet.

For example, it may be used as a multi-layer adhesive sheet having astructure in which a first adhesive layer and a second adhesive layerare directly or indirectly layered, at least the second adhesive layercomprising the adhesive sheet of the present invention, the amount offlow A and the thickness a μm of the first adhesive layer and the amountof flow B and the thickness b μm of the second adhesive layer having therelationships A×3<B and a×2<b. With regard to the multi-layer adhesivesheet, it is preferable that when a wafer, the adhesive sheet, and adicing tape are laminated together the side that is in contact with thewafer is the first adhesive layer, and the side that is in contact withthe dicing tape is the second adhesive layer.

By employing such a two layer sheet, it is possible to carry out bondingby appropriately selecting a pressure, temperature, and time (pressurein particular) for the bonding according to the absolute value of A or Bso that irregularities are embedded in the second layer and theirregularities do not pierce the first layer. That is, it is possible toensure the filling properties for wiring or wire and the insulationbetween the wiring or wire and an upper semiconductor chip. When A×B,the effect of the first adhesive layer in preventing the wiring or wirefrom penetrating is small, and there is a tendency for a circuit thatforms irregularities on a substrate or the wire to make contact with theabove positioned semiconductor chip, thus preventing the insulation frombeing guaranteed, and when a×2 b, there is a tendency for the fillingproperties for irregularities or wire to be degraded, thus easilycausing voids.

In the present invention, the amount of flow may be obtained by pressinga sample, formed by stamping an adhesive sheet prior to curing and a PETfilm into 1×2 cm strips, using a thermocompression bonding tester(manufactured by Tester Sangyo Co., Ltd.) at a hot plate temperature of100° C. and a pressure of 1 MPa for 18 seconds, and then measuring thelength of resin protruding from the edge of the sample using an opticalmicroscope.

Furthermore, it is possible, for example, to employ a multi-layeradhesive sheet having a structure in which a first adhesive layer and asecond adhesive layer are directly or indirectly layered, at least thesecond adhesive layer comprising the adhesive sheet of the presentinvention, and the melt viscosity a Pa·s and the thickness α μm of thefirst adhesive layer and the melt viscosity β Pa·s and the thickness bμm of the second adhesive layer having the relationships α>β×3 anda×2<b. With regard to the multi-layer adhesive sheet, it is preferablethat when a wafer, the adhesive sheet, and a dicing tape are laminatedtogether the side that is in contact with the wafer is the firstadhesive layer, and the side that is in contact with the dicing tape isthe second adhesive layer.

By employing such a two layer sheet, it is possible to carry out bondingby appropriately selecting a pressure, temperature, and time (pressurein particular) for the bonding according to the absolute value of α or βso that irregularities are embedded in the second layer and theirregularities do not pierce the first layer. That is, it is possible toensure the filling properties for wiring or wire and the insulationbetween the wiring or wire and an upper semiconductor chip. When a×3,the effect of the first adhesive layer in preventing the wiring or wirefrom penetrating is small, and there is a tendency for it to makecontact with a circuit that forms irregularities on a substrate or withthe semiconductor chip positioned above the wire, thus preventing theinsulation from being guaranteed, and when a×2 b, there is a tendencyfor the filling properties for irregularities or wire to be degraded,thus easily causing voids.

In the present invention, the melt viscosity may be obtained using aparallel plate plastometer method, which will be described later, bymeasuring and calculating for an adhesive sheet prior to curing.

It is preferable for A, B, α, β, a, and b to be in their respectiveappropriate ranges; A is preferably 100 to 400 μm, and B is preferably300 to 2,000 μm. When they are too low, the filling properties aredegraded, and when they are too high, the resin tends to protrude fromthe edge of the semiconductor chip to a great extent. α is preferably3,000 to 1,500,000 Pa·s. β is preferably 1,000 to 7,500 Pa·s,particularly preferably 1,000 to 5,000 Pa·s, and more preferably 1,500to 3,000 Pa·s. When they are too high, the filling properties aredegraded, and when they are too low, the resin tends to protrude fromthe edge of the semiconductor chip to a great extent. Furthermore, a ispreferably 5 to 30 μm, and b is preferably 10 to 250 μm. When theadhesive sheet is used as a single layer, it is preferable that theflow, the melt viscosity, and the thickness of the adhesive sheet on itsown are in the above-mentioned ranges specified for B, and b.

The first adhesive layer is not particularly limited as long as it canbe bonded to a wafer at 80° C. or below, and HIATTACH HS-210 and HS-230manufactured by Hitachi Chemical Co., Ltd., etc. may be used. As thesecond adhesive layer, the adhesive sheet of the present invention maybe used.

As a preferred example of a combination, HIATTACH HS-230 (amount of flow250 μm, thickness 10 μm, melt viscosity 320,000 Pa·s) and the adhesivesheet of the present invention (amount of flow 1,000 μm, thickness 70μm, melt viscosity 2,200 Pa·s) can be cited. In this case, therelationships A×3<B, α>β×3, and a×2<b are satisfied.

The adhesive sheet of the present invention may be used on its own, andas one embodiment it may be used as an integrated dicing tape-typeadhesive sheet in which the adhesive sheet of the present invention islayered on a conventionally known dicing tape. In this case, only onelamination step onto a wafer is required, and the operation can becarried out efficiently.

Examples of the dicing tape used in the present invention includeplastic films such as polytetrafluoroethylene film, polyethyleneterephthalate film, polyethylene film, polypropylene film,polymethylpentene film, and polyimide film. A surface treatment such asa primer coating, a UV treatment, a corona discharge treatment, apolishing treatment, or an etching treatment may be carried out asnecessary. The dicing tape preferably has tackiness; the above-mentionedplastic film to which tackiness has been imparted may be used, or atacky layer may be provided on one side of the above-mentioned plasticfilm. This can be formed by coating the film with a resin compositionhaving an appropriate tack strength, which is obtained by adjusting theratio of liquid components and the Tg of a high molecular weightcomponent in particular, and drying the coating.

Furthermore, when the adhesive sheet is used for production of asemiconductor device, it is desirable for it to have a tack strengthsuch that the semiconductor chips are not scattered during dicing andare released from the dicing tape during subsequent pickup. For example,if the tackiness of the adhesive sheet is too high, pickup might becomedifficult. It is therefore preferable to adjust the tack strength of theadhesive sheet as appropriate, and as a method therefor the tendency forthe adhesive strength and the tack strength to be increased as a resultof increasing the flow of the adhesive sheet at room temperature, andthe tendency for the adhesive strength and the tack strength to bedecreased as a result of decreasing the flow may be utilized. Forexample, in order to increase the flow, there are methods in which thecontent of a plasticizer is increased, the content of a tackifyingmaterial is increased, etc. In contrast thereto, in order to decreasethe flow, the contents of the above-mentioned compounds may bedecreased. Examples of the plasticizer include a monofunctional acrylicmonomer, a monofunctional epoxy resin, a liquid epoxy resin, an acrylicresin, and a so-called epoxy-based diluent.

As a method of layering an adhesive sheet on a dicing tape, in additionto printing, a method in which a preformed adhesive sheet is laminatedon a dicing tape by means of pressing or a hot roll can be cited, andthe method involving hot roll lamination is preferable since productioncan be carried out continuously and the efficiency is good.

The thickness of the dicing tape is not particularly limited; it isappropriately determined based on the knowledge of a person skilled inthe art according to the film thickness of the adhesive sheet or theintended application of an integrated dicing tape-type adhesive sheet,and is 60 to 150 μm, and preferably 70 to 130 μm, since it is economicaland the handling properties of the film are good.

The adhesive sheet of the present invention is preferably used inproduction of a semiconductor device, and more preferably insemiconductor device production comprising steps of laminating togethera wafer, an adhesive sheet, and a dicing tape at 0° C. to 80° C., thencutting the wafer, the adhesive sheet, and the dicing tapesimultaneously by means of a rotating blade to give an adhesive-equippedsemiconductor chip, and then bonding this adhesive-equippedsemiconductor chip to a substrate or a semiconductor chip havingirregularities at a load of 0.001 to 1 MPa so as to fill theirregularities with adhesive.

In the present invention, as the wafer, in addition to monocrystallinesilicon, polycrystalline silicon, various types of ceramic, or acompound semiconductor such as gallium arsenide, etc. may be used.

When the adhesive sheet is used as a single layer, after the adhesivesheet is laminated to the wafer, the dicing tape may be laminated to theadhesive sheet side. When the adhesive sheet is used in multiple layers,a first adhesive layer and a second adhesive layer may be laminated tothe wafer in sequence, or a multi-layer adhesive sheet may be formed inadvance from the first adhesive layer and the second adhesive layer, andthis multi-layer adhesive sheet may be then laminated to the wafer. Inaccordance with the use of an integrated dicing tape-type adhesive sheetcomprising the adhesive sheet or the multi-layer adhesive sheet of thepresent invention, and the dicing tape, a semiconductor device may alsobe produced.

A temperature at which the adhesive sheet is affixed to the wafer, thatis, a lamination temperature, is 0° C. to 80° C., preferably 15° C. to80° C., and more preferably 20° C. to 70° C. When it exceeds 80° C.,distortion of the wafer after laminating the adhesive sheet tends tobecome large.

When the dicing tape or the integrated dicing tape-type adhesive sheetis laminated, it is preferable for it to be carried out at theabove-mentioned temperature.

FIG. 3 shows a sectional view of an adhesive sheet b, a semiconductorwafer A, and a dancing tape 1 of one embodiment of the presentinvention, and FIG. 4 shows a sectional view of a multi-layer adhesivesheet c, the semiconductor wafer A, and the dicing tape 1 of oneembodiment of the present invention. In FIG. 4, a denotes a firstadhesive layer, and b′ denotes a second adhesive layer.

Subsequently, the semiconductor wafer to which are laminated theadhesive sheet and the dicing tape is diced using a dicing cutter, thenwashed, and dried, thus giving an adhesive-equipped semiconductor chip.

As another embodiment, the adhesive sheet of the present invention maybe used as a substrate film-equipped adhesive sheet in which an adhesivesheet b is provided on a substrate film 5 as shown in FIG. 6. By sodoing, it is convenient even when the adhesive sheet is difficult tohandle on its own; for example, by laminating the adhesive sheet of thestructure in FIG. 6 to the above-mentioned dicing tape, then peeling offthe substrate film 5, and subsequently laminating to the semiconductorwafer A, the structure shown in FIG. 3 can easily be achieved. It isalso possible to use the substrate film 5 as a cover film withoutpeeling it off.

The above-mentioned substrate film 5 is not particularly limited, andexamples thereof include polyester film, polypropylene film,polyethylene terephthalate film, polyimide film, polyetherimide film,polyether naphthalate film, and methylpentene film.

Furthermore, the adhesive sheet of the present invention may be used asa substrate film-equipped adhesive sheet in which multiple layers ofadhesive sheets are provided on a substrate film in the order: secondadhesive layer b′, first adhesive layer a, as shown in FIG. 7. They mayalso be layered on the substrate film in the order: first adhesive layera, second adhesive layer b′.

As another embodiment, the adhesive sheet of the present invention mayhave a structure shown in FIG. 6 and FIG. 7 and the adhesive sheetitself may function as a dicing tape. Such an adhesive sheet is calledan integrated dicing/die-bonding type adhesive sheet, etc., and sincethe single sheet functions both as a dicing tape and as an adhesivesheet, an adhesive-equipped semiconductor chip can be obtained as shownin FIG. 8 by just dicing and pickup.

In order to impart such functions to the adhesive sheet, for example,the adhesive sheet may contain a photocuring component such as aphotocuring high molecular weight component, a photocuring monomer, or aphotoinitiator. Such an integrated-type sheet has been subjected toirradiation with light when the semiconductor chip is bonded to thesubstrate or the semiconductor chip, and a value for the storage modulusby a dynamic viscoelasticity measurement at 25° C. prior to curing and avalue for the storage modulus by a dynamic viscoelasticity measurementat 80° C. prior to curing denote values in a stage that is afterirradiation with light and before thermosetting.

The integrated dicing/die bonding-type adhesive sheet is preferably usedin production of a semiconductor device comprising steps of laminatingtogether a wafer, an adhesive sheet, and a dicing tape at 0° C. to 80°C., then cutting the wafer, the adhesive sheet, and the dicing tapesimultaneously by means of a rotating blade to give an adhesive-equippedsemiconductor chip, and then bonding this adhesive-equippedsemiconductor chip to a substrate or a semiconductor chip havingirregularities at a load of 0.001 to 1 MPa so as to fill theirregularities with adhesive.

The adhesive-equipped semiconductor chip A1 thus obtained is bonded to asubstrate 3 having irregularities due to wiring 4 or a semiconductorchip having irregularities due to a wire 2 via an adhesive b1 at a loadof 0.001 to 1 MPa, and the irregularities are filled by the adhesive(FIG. 5). The load is preferably 0.01 to 0.5 MPa, and more preferably0.01 to 0.3 MPa. When the load is less than 0.001 MPa, there is atendency for voids to occur and the heat resistance to be degraded, andwhen it exceeds 1 MPa, there is a tendency for the semiconductor chip tobreak.

FIG. 5 is a schematic drawing showing one example of a step of bondingan adhesive-equipped semiconductor chip to a wire-bonded semiconductorchip.

In the present invention, when the adhesive-equipped semiconductor chipis bonded to a substrate or a semiconductor chip, it is preferable toheat irregularities due to wiring of the substrate, wires of thesemiconductor chip, etc. The heating temperature is preferably 60° C. to240° C., and more preferably 100° C. to 180° C. When it is less than 60°C., the bonding properties tend to deteriorate, and when it exceeds 240°C., there is a tendency for the substrate to deform, and distortion toincrease. Examples of the heating method include a method in which thesubstrate or the semiconductor chip is put into contact with a preheatedhot plate, a method in which the substrate or the semiconductor chip isirradiated with infrared rays or microwaves, and a method in which it isexposed to hot air.

In the present invention, in accordance with use of an adhesive sheethaving a specified resin composition, it is possible to prevent cuttingwaste formed when cutting the adhesive sheet or the wafer by means of arotating blade during dicing from becoming detached in a filamentousstate from the dicing tape during washing or pickup after cutting.Furthermore, an adhesive sheet having a multi-layer structure,particularly one in which a layer having low flow and a layer havinghigh flow are layered or one in which a layer having a high meltviscosity and a layer having a low melt viscosity are layered, hasexcellent filling properties for a wiring circuit and wire and excellentinsulation from upper and lower semiconductor chips. Furthermore, sincethe adhesive sheet of the present invention has good filling propertiesfor a wiring circuit and wire and excellent cutting properties during adicing step in production of a semiconductor device in which the waferand the adhesive sheet are simultaneously cut, the speed of dicing canbe increased. Because of this, in accordance with the adhesive sheet ofthe present invention, it is possible to improve the yield of thesemiconductor device and enhance the production speed.

Moreover, the adhesive sheet of the present invention may be used as anadhesive sheet having excellent adhesion reliability in a step ofbonding a semiconductor chip to a supporting member such as a substrateor a lower layer chip in production of a semiconductor device. That is,the adhesive sheet of the present invention has the heat resistance,moisture resistance, and insulation that are required when mounting asemiconductor chip on a supporting member for mounting a semiconductor,and has excellent workability.

EXAMPLES Composition of Adhesive Sheet and Production Process Example 1

A composition containing 30 parts by weight of a bisphenol F epoxy resin(epoxy equivalent 160, product name YD-8170C, manufactured by TohtoKasei Co., Ltd.) and 10 parts by weight of a cresol novolac epoxy resin(epoxy equivalent 210, product name YDCN-703, manufactured by TohtoKasei Co., Ltd.) as epoxy resins; 27 parts by weight of a phenol novolacresin (product name Plyophen LF2882, manufactured by Dainippon Ink andChemicals, Incorporated) as a curing agent for the epoxy resin; 28 partsby weight of an epoxy group-containing acrylic rubber (weight-averagemolecular weight by gel permeation chromatography 800,000, 3 wt % ofglycidyl methacrylate, Tg −7° C., product name HTR-860P-3DR manufacturedby Nagase chemteX Corporation) as an epoxy group-containing acryliccopolymer; 0.1 parts by weight of an imidazole-based curing accelerator(Curezol 2PZ-CN manufactured by Shikoku Chemicals Corporation) as acuring accelerator; 95 parts by weight of a silica filler (manufacturedby Admafine Corp., S0-C2 (specific gravity: 2.2 g/cm³, Mohs' hardness 7,average particle size 0.5 μm, specific surface area 6.0 m²/g)); and 0.25parts by weight (product name A-189, manufactured by Nippon Unicar Co.,Limited) and 0.5 parts by weight (product name A-1160, manufactured byNippon Unicar Co., Limited) as silane coupling agents was added to andmixed with cyclohexanone while stirring, and degassing in vacuum wascarried out to give an adhesive varnish.

This adhesive varnish was applied on a 50 μm thick release-treatedpolyethylene terephthalate film, drying was carried out by heating at90° C. for 10 minutes and at 120° C. for 5 minutes to give a coatingwith a film thickness of 75 μm, and an adhesive sheet in a B-stage statewas thus prepared. The flow of this film was 757 μm.

The adhesive sheet b was laminated at 60° C. to a semiconductor wafer A(thickness 80 μm) that was to be processed, and the edges were cut off.This was laminated with a dicing tape 1 by means of a hot roll laminator(Riston, manufactured by Du Pont) at 25° C. (FIG. 3). The dicing tapewas UC3004M-80 manufactured by The Furukawa Electric Co., Ltd. The filmthickness of the dicing tape was 100 μm.

Example 2

HS-230 (thickness 10 μm) as a first adhesive layer and the same adhesivesheet as in Example 1 as a second adhesive layer were laminated at 60°C. to give a multi-layer adhesive sheet having first and second adhesivelayers. When the amount of flow was measured in a state in which thefirst adhesive layer and the second adhesive layer were laminatedtogether, the first adhesive layer was 200 μm, and the second adhesivelayer was 758 μm.

The multi-layer adhesive sheet was laminated at 60° C. to asemiconductor wafer A (thickness 80 μm) that was to be processed so thatthe second adhesive layer was in contact with the semiconductor wafer A,and the edges were cut off. The dicing tape 1 was placed on this so thatthe second adhesive layer b was layered on the dicing tape 1, and theywere laminated at 25° C. by means of a hot roll laminator (Riston,manufactured by Du Pont) (FIG. 4). The dicing tape was UC3004M-80manufactured by The Furukawa Electric Co., Ltd. The film thickness ofthe dicing tape was 100 μm.

Example 3

An adhesive sheet was prepared in the same manner as in Example 1 exceptthat the film thickness was 50 μm.

Comparative Example 1

A sample was prepared in the same manner as in Example 1 except that thefiller was not used. The flow of the adhesive sheet was 2,000 μm.

Examples 4 to 8 and Comparative Examples 2 and 3

Adhesive sheets were prepared in the same manner as in Example 1 exceptthat the contents of the filler and the epoxy group-containing acrylicrubber were changed to the amounts shown in Table 1.

Evaluation (1) Modulus of Elasticity Subsequent to Curing

The modulus of elasticity at 170° C. of an adhesive sheet in a C-stagestate was measured using a dynamic viscoelastometer (DVE-V4,manufactured by Rheology Co., Ltd.) (sample size: length 20 mm, width 4mm, temperature range −30° C. to 200° C., rate of temperature increase5° C./min, tensile mode, 10 Hz, automatic static load).

(2) Bonding Strength

A semiconductor chip (5 mm square) was bonded onto a gold-platedsubstrate (copper foil-equipped flexible substrate electrolytic goldplated (Ni: 5 μm, Au: 0.3 μm)) using an adhesive sheet on a hot plate at120° C., and cured at 130° C. for 30 minutes +170° C. for 1 hour. Thissample was subjected to a measurement of shear strength at 260° C. aftermoisture absorption at 85° C./85% RH for 48 hours.

(3) Lamination Properties

An adhesive sheet with a width of 10 mm and a wafer were laminatedtogether by means of a hot roll laminator (60° C., 0.3 m/minutes, 0.3MPa), and subsequently a 90° peel strength was determined in which theadhesive sheet was peeled off at an angle of 90° at a tensile speed of50 mm/minute using a UTM-4-100 tensilon manufactured by TOYOBALWIN in anatmosphere at 25° C. When the 90° peel strength was 30 N/m or greater,the lamination properties were good (◯), and when the 90° peel strengthwas less than 30 N/m, the lamination properties were poor (X).

(4) Flow

The amount of flow was defined as a value obtained by pressing a sample,formed by stamping an adhesive sheet and a PET film into 1×2 cm strips,using a thermocompression bonding tester (manufactured by Tester SangyoCo., Ltd.) at a hot plate temperature of 100° C. and a pressure of 1 MPafor 18 seconds, and then measuring the length of resin protruding fromthe edge of the sample using an optical microscope.

(5) Dicing Properties

The adhesive sheet and dicing tape-equipped semiconductor wafer wasdiced using a dicing cutter, then washed, and dried to give an adhesivesheet-equipped semiconductor chip. The maximum height of cracks on theside of the semiconductor chip and the length of resin burrs weremeasured, and an evaluation of “◯” was given when they were 30 μm orless and “X” when they exceeded 30 μm.

(6) Filling Properties, Reflow Crack Resistance, Temperature CycleResistance

A semiconductor device sample was prepared by bonding anadhesive-equipped semiconductor chip and a wiring substrate thatemployed a 25 μm thick polyimide film as a substrate and had 10 μm highirregularities under conditions of 0.1 MPa, 1 s, and 160° C. (solderball formed on one side), and the filling properties and the heatresistance were examined. Evaluation of the filling properties wascarried out by polishing a cross section of the semiconductor chip,examining the area around irregularities of the wiring substrate usingan optical microscope, and checking for the presence or absence of voidshaving a diameter of 5 μm or greater. An evaluation of “◯” was givenwhen there were no voids having a diameter of 5 μm or greater, and “X”when there were. Reflow crack resistance and temperature cycleresistance tests were employed as methods of evaluating the heatresistance.

Evaluation of the reflow crack resistance was carried out by examiningcracks in a sample by eye and an ultrasonic microscope when subjectedtwice to a treatment involving passing the sample through an IR reflowfurnace whose temperature was set so that the maximum temperature of thesample surface was maintained at 260° C. for 20 seconds and cooling byleaving it to stand at room temperature. An evaluation of “◯” was givenwhen all 10 samples had no cracks and “X” when at least one sample had acrack.

Evaluation of the temperature cycle resistance was carried out by 1,000cycles of a step of leaving a sample in an atmosphere at −55° C. for 30minutes and subsequently leaving it in an atmosphere at 125° C. for 30minutes, and was “0” if all 10 samples had no damage such as peeling offor cracks when examined using an ultrasonic microscope, and “X” if atleast one occurred.

(7) Wire Filling Properties

The filling properties were evaluated for a sample formed by bondingtogether, under conditions of 0.1 MPa, 1 s, and 160° C., a semiconductorchip, an adhesive sheet, and a semiconductor chip having a gold wire(diameter 25 μm) laid on the semiconductor chip at a height of 60 μm. Across section of the semiconductor chip was polished, and the presenceor absence of voids having a diameter of 5 μm or greater in the vicinityof the wire was checked using an optical microscope. An evaluation of“◯” was given when there were no voids having a diameter of 5 μm orgreater and “X” when there were.

(8) Modulus of Elasticity Prior to Curing

The modulus of elasticity at 25° C. and 80° C. of the adhesive sheet ina B-stage state was measured using a dynamic viscoelastometer (DVE-V4,manufactured by Rheology Co., Ltd.) (sample size: length 20 mm, width 4mm, temperature range −30° C. to 200° C., rate of temperature increase5° C./min, tensile mode, 10 Hz, automatic static load).

(9) Melt Viscosity

The melt viscosity of the adhesive sheet was measured and calculated bythe parallel plate plastometer method below. That is, adhesive sheetswere laminated to give a 100 to 300 μm thick film. A sample was preparedby stamping this into a circle having a diameter of 11.3 mm and it waspressurized at 100° C. with a load of 3.0 kgf for 5 seconds, and themelt viscosity was determined using Equation 1 from the thickness of thesample before and that after the pressurization. For the film of Example2, the melt viscosity of each layer was measured; the first adhesivelayer had a melt viscosity of 320,000 Pa·s, and the second adhesivelayer had a melt viscosity of 2,640 Pa·s.

$\begin{matrix}\left\lbrack {{Equation}\mspace{14mu} 1} \right\rbrack & \; \\{t = {\eta \frac{3V^{2}}{8\pi \; F}\left( {\frac{1}{z^{4}} - \frac{1}{{zo}^{4}}} \right)}} & {{Formula}\mspace{14mu} 1}\end{matrix}$

(In the formula, Z0 is the thickness of the adhesive sheet beforeapplying a load, Z is the thickness of the adhesive sheet after applyingthe load, V is the volume of the adhesive sheet, F is the load applied,and t is the time for which the load is applied.)

A method of preparing a sample is explained in detail. When thethickness of a single adhesive sheet was less than 100 μm, a pluralityof the adhesive sheets were bonded together to give a thickness of 100to 300 μm. This is because when the thickness is 100 to 300 μm, thereproducibility of measurement is good. For example, when the thicknessof a single adhesive sheet is 40 μm, 3 to 7 adhesive sheets may bebonded together. The conditions for bonding together depend on thesample; they are bonded together so that no peel off occurs duringmeasurement at the interface where they are bonded together, and theconditions are normally such that the adhesive sheet does not cure.

Evaluation results are given in Table 1.

TABLE 1 Examples Item Units 1 2 3 4 5 6 7 8 HTR-860P-3 Parts by weight28 28 28 44 33 32 28 44 S0-C2 Parts by weight 95 95 95 47 66 177 41 110High molecular weight component wt % 29 29 29 40 33 32 29 40 Filler(relative to 100 parts by weight of resin) Parts by weight 100 100 10042 66 179 43 99 Film thickness μm 75 75 50 75 75 75 75 75 Stage Cmodulus of elasticity (170° C.) MPa 160 120 160 50 90 200 100 140Adhesive strength kg 2 2.3 2 1.8 2 1.6 1.8 2.2 Lamination properties — ◯◯ ◯ ◯ ◯ ◯ ◯ ◯ Flow μm 757 758 759 760 1200 770 1800 680 Dicingproperties — ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Filling properties — ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Reflowcrack resistance — ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Temperature cycle resistance — ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ Wire filling properties — ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Melt viscosity (100°C.) Pa · S 2640 2640 2630 2630 1660 2600 1110 2940 Stage B modulus ofelasticity (25° C.) MPa 600 580 614 340 380 900 320 560 Stage B modulusof elasticity (80° C.) MPa 1 1 1.4 0.8 0.3 1.9 0.8 1.1 ComparativeExamples Item Units 1 2 3 HTR-860P-3 Parts by weight 28 66 66 S0-C2Parts by weight 0 253 57 High molecular weight component wt % 29 50 50Filler (relative to 100 parts by weight of resin) Parts by weight 0 19043 Film thickness μm 75 75 75 Stage C modulus of elasticity (170° C.)MPa 40 800 30 Adhesive strength kg 1.6 0.1 2.6 Lamination properties — ◯X ◯ Flow μm 2000 130 340 Dicing properties — X X X Filling properties —◯ X X Reflow crack resistance — ◯ X ◯ Temperature cycle resistance — ◯ X◯ Wire filling properties — ◯ X X Melt viscosity (100° C.) Pa · S 98015380 7700 Stage B modulus of elasticity (25° C.) MPa 200 1200 600 StageB modulus of elasticity (80° C.) MPa 0.05 15 3

Examples 1 to 8 exhibited good dicing properties and good fillingproperties for irregularities of the substrate and wire. ComparativeExamples 1 to 3 all exhibited poor dicing properties.

As hereinbefore described, the present invention is explained by way ofexamples, and it has been found that the following effects can beexhibited. When the adhesive sheet of the present invention is used, ina dicing step of production of a semiconductor device, a wafer and theadhesive sheet can be cut well. The semiconductor chips do not fly offduring dicing, and the ease of pickup is also good. Furthermore, in astep of bonding a semiconductor chip, a substrate having irregularities,and a wire-equipped semiconductor chip, filling properties areexcellent, and when mounting a semiconductor chip on a supporting memberfor mounting a semiconductor, the required heat resistance and moistureresistance are obtained, and the workability is excellent. From theseresults, in accordance with the adhesive sheet of the present invention,it is possible to improve the reliability of a semiconductor device andenhance the processing speed and the yield of a semiconductor device.

1. An adhesive sheet comprising: 100 parts by weight of a resin comprising 15 to 40 wt of a high molecular weight component containing a crosslinking functional group and having a weight-average molecular weight of 100,000 or greater and a Tg of −50° C. to 50° C., and 60 to 85 wt % of a thermosetting component containing an epoxy resin as a main component; and 40 to 180 parts by weight of a filler, the adhesive sheet having a thickness of 10 to 250 μm.
 2. The adhesive sheet according to claim 1, wherein prior to curing, the storage modulus by a dynamic viscoelasticity measurement at 25° C. is 200 to 3,000 MPa, and the storage modulus by a dynamic viscoelasticity measurement at 80° C. is 0.1 to 10 MPa.
 3. The adhesive sheet according to claim 1, wherein the storage modulus by a dynamic viscoelasticity measurement at 170° C. subsequent to curing is 20 to 600 MPa.
 4. The adhesive sheet according to claim 1, wherein the melt viscosity at 100° C. prior to curing is 1,000 to 7,500 Pa·s.
 5. The adhesive sheet according to claim 1, which comprises 100 parts by weight of the resin and 60 to 120 parts by weight of the filler.
 6. The adhesive sheet according to claim 1, wherein the filler has a Mohs' hardness of 3 to
 8. 7. The adhesive sheet according to claim 1, wherein the filler has an average particle size of 0.05 to 5 μm and a specific surface area of 2 to 200 m²/g. 